123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400 |
- 'use strict';
- var zlib_deflate = require('./zlib/deflate');
- var utils = require('./utils/common');
- var strings = require('./utils/strings');
- var msg = require('./zlib/messages');
- var ZStream = require('./zlib/zstream');
- var toString = Object.prototype.toString;
- var Z_NO_FLUSH = 0;
- var Z_FINISH = 4;
- var Z_OK = 0;
- var Z_STREAM_END = 1;
- var Z_SYNC_FLUSH = 2;
- var Z_DEFAULT_COMPRESSION = -1;
- var Z_DEFAULT_STRATEGY = 0;
- var Z_DEFLATED = 8;
- function Deflate(options) {
- if (!(this instanceof Deflate)) return new Deflate(options);
- this.options = utils.assign({
- level: Z_DEFAULT_COMPRESSION,
- method: Z_DEFLATED,
- chunkSize: 16384,
- windowBits: 15,
- memLevel: 8,
- strategy: Z_DEFAULT_STRATEGY,
- to: ''
- }, options || {});
- var opt = this.options;
- if (opt.raw && (opt.windowBits > 0)) {
- opt.windowBits = -opt.windowBits;
- }
- else if (opt.gzip && (opt.windowBits > 0) && (opt.windowBits < 16)) {
- opt.windowBits += 16;
- }
- this.err = 0;
- this.msg = '';
- this.ended = false;
- this.chunks = [];
- this.strm = new ZStream();
- this.strm.avail_out = 0;
- var status = zlib_deflate.deflateInit2(
- this.strm,
- opt.level,
- opt.method,
- opt.windowBits,
- opt.memLevel,
- opt.strategy
- );
- if (status !== Z_OK) {
- throw new Error(msg[status]);
- }
- if (opt.header) {
- zlib_deflate.deflateSetHeader(this.strm, opt.header);
- }
- if (opt.dictionary) {
- var dict;
-
- if (typeof opt.dictionary === 'string') {
-
- dict = strings.string2buf(opt.dictionary);
- } else if (toString.call(opt.dictionary) === '[object ArrayBuffer]') {
- dict = new Uint8Array(opt.dictionary);
- } else {
- dict = opt.dictionary;
- }
- status = zlib_deflate.deflateSetDictionary(this.strm, dict);
- if (status !== Z_OK) {
- throw new Error(msg[status]);
- }
- this._dict_set = true;
- }
- }
- Deflate.prototype.push = function (data, mode) {
- var strm = this.strm;
- var chunkSize = this.options.chunkSize;
- var status, _mode;
- if (this.ended) { return false; }
- _mode = (mode === ~~mode) ? mode : ((mode === true) ? Z_FINISH : Z_NO_FLUSH);
-
- if (typeof data === 'string') {
-
- strm.input = strings.string2buf(data);
- } else if (toString.call(data) === '[object ArrayBuffer]') {
- strm.input = new Uint8Array(data);
- } else {
- strm.input = data;
- }
- strm.next_in = 0;
- strm.avail_in = strm.input.length;
- do {
- if (strm.avail_out === 0) {
- strm.output = new utils.Buf8(chunkSize);
- strm.next_out = 0;
- strm.avail_out = chunkSize;
- }
- status = zlib_deflate.deflate(strm, _mode);
- if (status !== Z_STREAM_END && status !== Z_OK) {
- this.onEnd(status);
- this.ended = true;
- return false;
- }
- if (strm.avail_out === 0 || (strm.avail_in === 0 && (_mode === Z_FINISH || _mode === Z_SYNC_FLUSH))) {
- if (this.options.to === 'string') {
- this.onData(strings.buf2binstring(utils.shrinkBuf(strm.output, strm.next_out)));
- } else {
- this.onData(utils.shrinkBuf(strm.output, strm.next_out));
- }
- }
- } while ((strm.avail_in > 0 || strm.avail_out === 0) && status !== Z_STREAM_END);
-
- if (_mode === Z_FINISH) {
- status = zlib_deflate.deflateEnd(this.strm);
- this.onEnd(status);
- this.ended = true;
- return status === Z_OK;
- }
-
- if (_mode === Z_SYNC_FLUSH) {
- this.onEnd(Z_OK);
- strm.avail_out = 0;
- return true;
- }
- return true;
- };
- Deflate.prototype.onData = function (chunk) {
- this.chunks.push(chunk);
- };
- Deflate.prototype.onEnd = function (status) {
-
- if (status === Z_OK) {
- if (this.options.to === 'string') {
- this.result = this.chunks.join('');
- } else {
- this.result = utils.flattenChunks(this.chunks);
- }
- }
- this.chunks = [];
- this.err = status;
- this.msg = this.strm.msg;
- };
- function deflate(input, options) {
- var deflator = new Deflate(options);
- deflator.push(input, true);
-
- if (deflator.err) { throw deflator.msg || msg[deflator.err]; }
- return deflator.result;
- }
- function deflateRaw(input, options) {
- options = options || {};
- options.raw = true;
- return deflate(input, options);
- }
- function gzip(input, options) {
- options = options || {};
- options.gzip = true;
- return deflate(input, options);
- }
- exports.Deflate = Deflate;
- exports.deflate = deflate;
- exports.deflateRaw = deflateRaw;
- exports.gzip = gzip;
|